Houston Astros catcher Evan Gattis (11) is tended to after being hit by the back swing of Tampa Bay Rays Corey Dickerson during the eighth inning of an MLB game at Minute Maid Park, Thursday, Aug. 3, 2017, in

Tampa Bay Rays Evan Longoria (3) flies into home to score a run against Houston Astros catcher Evan Gattis (11) on a Steven Souza Jr. RBI double in the seventh inning of an MLB game at Minute Maid Park,

Toronto Blue Jays Norichika Aoki (23) tips his hat to the Houston Astros fans cheering him as he batted during the ninth inning of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in Houston. ( Karen

Toronto Blue Jays Norichika Aoki (23) tips his hat to the Houston Astros fans cheering him as he batted during the ninth inning of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in Houston. ( Karen

Toronto Blue Jays Norichika Aoki (23) tips his hat to the Houston Astros fans cheering him as he batted during the ninth inning of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in Houston. ( Karen

Toronto Blue Jays Norichika Aoki (23) tips his hat to the Houston Astros fans cheering him as he batted during the ninth inning of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in Houston. ( Karen

Houston Astros Yuli Gurriel (10) celebrates his two-run home run with Josh Reddick (22) during the first inning of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in Houston. ( Karen Warren / Houston

Houston Astros Tyler White (13) smiles as he crosses home plate after hitting his second home run of the night during the eighth inning of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in Houston. ( Karen Warren / Houston Chronicle )

Houston Astros Tyler White (13) smiles as he crosses home plate after hitting his second home run of the night during the eighth inning of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in Houston. (

Houston Astros Tyler White (13) smiles as he crosses home plate after hitting his second home run of the night during the eighth inning of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in Houston. ( Karen Warren / Houston Chronicle )

Houston Astros Tyler White (13) smiles as he crosses home plate after hitting his second home run of the night during the eighth inning of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in Houston. (

Houston Astros Yuli Gurriel (10) consoles Alex Bregman (2) after he flied out to end the fourth inning with the bases loaded during an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in Houston. ( Karen

Houston Astros Alex Bregman (2) watches his ball head of the wall with the bases loaded, only to fly out to end the fourth inning of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in Houston. ( Karen Warren / Houston Chronicle )

Houston Astros Alex Bregman (2) watches his ball head of the wall with the bases loaded, only to fly out to end the fourth inning of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in Houston. ( Karen

Houston Astros second baseman Marwin Gonzalez (9) tries to get the ball out of his hand as Toronto Blue Jays Ezequiel Carrera singled during the fourth inning of an MLB game at Minute Maid Park, Friday, Aug. 4,

Houston Astros second baseman Marwin Gonzalez (9) tries to get the ball out of his hand as Toronto Blue Jays Ezequiel Carrera singled during the fourth inning of an MLB game at Minute Maid Park, Friday, Aug. 4,

Houston Astros Josh Reddick (22) dives back to second base s Toronto Blue Jays shortstop Ryan Goins (17) attempted to tag him out during the third inning of an MLB game at Minute Maid Park, Friday, Aug. 4,

Houston Astros shortstop Alex Bregman (2) makes the throw to first base as Toronto Blue Jays Ryan Goins ground out during the third inning of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in Houston. (

Houston Astros shortstop Alex Bregman (2) makes the throw to first base as Toronto Blue Jays Justin Smoak ground out during the second inning of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in

Houston Astros shortstop Alex Bregman (2) makes the throw to first base as Toronto Blue Jays Ryan Goins ground out during the third inning of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in Houston. (

Behind home plate painted to celebrate Jeff Bagwell's induction into the Hall of Fame during the first inning of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in Houston. ( Karen Warren / Houston Chronicle )

Behind home plate painted to celebrate Jeff Bagwell's induction into the Hall of Fame during the first inning of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in Houston. ( Karen Warren / Houston

Houston Astros Marwin Gonzalez (9) runs up the line watching his home run ball go over the fence during the fourth inning of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in Houston. ( Karen Warren / Houston Chronicle )

Houston Astros Marwin Gonzalez (9) runs up the line watching his home run ball go over the fence during the fourth inning of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in Houston. ( Karen Warren /

Houston Astros second baseman Marwin Gonzalez (9) tries to tag Toronto Blue Jays Steve Pearce as he stole second base during the fourth inning of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in

Houston Astros Alex Bregman (2) watches as his ball heads for the wall for a two-run home run during the fourth inning of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in Houston. ( Karen Warren / Houston Chronicle )

Houston Astros Alex Bregman (2) watches as his ball heads for the wall for a two-run home run during the fourth inning of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in Houston. ( Karen Warren /

Toronto Blue Jays Steve Pearce laughs after Houston Astros second baseman Marwin Gonzalez (9) tried to tag him out after he stole second base during the fourth inning of an MLB game at Minute Maid Park, Friday,

Houston Astros second baseman Marwin Gonzalez (9) tries to get the ball out of his hand as Toronto Blue Jays Ezequiel Carrera singled during the fourth inning of an MLB game at Minute Maid Park, Friday, Aug. 4,

Houston Astros Marwin Gonzalez (9) celebrates his home run in the dugout during the fourth inning of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in Houston. ( Karen Warren / Houston Chronicle )

Houston Astros Marwin Gonzalez (9) celebrates his home run in the dugout during the fourth inning of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in Houston. ( Karen Warren / Houston Chronicle )

Former Astros and current Toronto Blue Jays left fielder Norichika Aoki (23) walks out of the dugout during batting practice before the start of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in Houston. ( Karen Warren / Houston Chronicle )

Former Astros and current Toronto Blue Jays left fielder Norichika Aoki (23) walks out of the dugout during batting practice before the start of an MLB game at Minute Maid Park, Friday, Aug. 4, 2017, in

Gattis was inadvertently hit in the mask by the back swing of Tampa Bay's Corey Dickerson in the eighth inning of Thursday's game.

The Astros recalled catcher Juan Centeno from Class AAA and sent down first baseman A.J. Reed.Initially, neither Gattis nor the team expected a concussion to send him to the disabled list.

"That part's scary," manager A.J. Hinch said before Saturday's game against the Blue Jays. "Obviously we thought he was going to be OK. Then the next day it felt a little bit worse."

Hinch, a former major league catcher, had to catch Brad Peacock's warmup pitches while Brian McCann put his gear on before the sixth inning Friday because Gattis' symptoms had worsened 24 hours after being whacked by Dickerson's swing.

"His (concussion) was a very difficult one to assess because he had no concussion symptoms when the play happened. After the game had no concussion symptoms when he saw the doctor. Woke up next day and had concussion symptoms."